1. Field of the Invention.
The present invention relates generally to a digital electronic apparatus for generating simulated scan patterns of a conventional radar antenna.
2. Description of the Prior Art.
Radar systems normally employ directive antennas for transmission and reception and the gain of these antennas is a function of the angular distance of the target from the axis of maximum sensitivity of the antenna. In practice, the target will be on the axis of maximum antenna gain for only a short period of time, and as the antenna scans past the target the amplitude of the radiated pulses as seen by the target will be modulated by the shape of the antenna gain pattern.
The problem of generating a series of pulses whose amplitude varies according to a particular antenna pattern has been solved by prior art devices utilizing electromechanical techniques. These electromechanical devices have significant drawbacks that are inherent in their modes of operation. Most such devices include a motor driving a shaped potentiometer. These devices are expensive, subject to wear on the movable parts and are able to generate only one pattern shape.